1. Field of the Invention
The present invention relates to eyeglasses and more particularly to eyeglasses having readily releasable lens holders.
2. Prior Art
Conventional one-piece plastic eyeglass frames generally require that eyeglass lenses be specially beveled so that they can be heated and snapped into place. It is quite common for such lenses to pop out of their frames, when the frames are inadvertently jarred, dropped, struck etc. usually with consequent damage to the lenses. Once a lens has popped out of the frame, it is in any event difficult for the user to reinsert it in the frame. Normally, the user must return the eyeglasses to the optometrist or optician for repair.
Metal rim-type eyeglasses usually secure the lenses in place by screwing parts of the rims together with very small screws which normally are very difficult to loosen and tighten, even if special tiny screwdrivers are available.
In order to reduce the cost of eyeglass assembly, repair and replacement it would be desirable to provide a simple, inexpensive mechanism for rapidly and easily releasing the lenses from the eyeglass frame and for reinserting them into the frame. Such mechanism would permit the switching of lenses by the user at will, for example, reading purposes with those for sun shielding purposes, or for drawing purposes, or safety shielding, etc., while utilizing the same frame.
Although several mechanism have been devised for such purposes, they are generally expensive, complicated, inefficient, bulky and unsightly. See, for example, U.S. Pat. No. 4,176,921, wherein such a mechanism is disclosed, which projects up well above the level of the frame, is complicated and may interfere with vision as well as the overall appearance of the frame. Therefore, the need remains for a simpler, more efficient device for permitting rapid efficient removal of lenses from and insertion of lenses into eyeglass frames.